Oxidative dehydrogenation coproduction

Patent metadata

Field	Value
Publication number	US-11760704-B2
Application number	US-202017630000-A
Country	US
Kind code	B2
Filing date	Aug 17, 2020
Priority date	Aug 28, 2019
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A system and method for coproduction in the production of ethylene, including contacting ethane with an oxidative dehydrogenation (ODH) catalyst in presence of oxygen in a first reactor to dehydrogenate ethane to ethylene, and contacting a first-reactor effluent with an ODH catalyst in a second reactor to form ethanol and acetaldehyde.

First claim

The invention claimed is:

1. A method, comprising:
contacting ethane with a first oxidative dehydrogenation (ODH) catalyst in presence of oxygen in a first reactor to produce a first-reactor effluent comprising ethylene, carbon dioxide, and water;
removing oxygen from the first-reactor effluent upstream of a second reactor to provide a modified first-reactor effluent;
passing the modified first-reactor effluent from the first reactor to the second reactor; and
contacting the modified first-reactor effluent with a second ODH catalyst in the second reactor to form
a second-reactor effluent comprising ethylene, ethanol, and acetaldehyde.

2. The method of claim 1 , further comprising:
maintaining an operating temperature of the first reactor at less than 450° C.; and
maintaining an operating temperature of the second reactor at less than 450° C.,
wherein the second-reactor effluent further comprises carbon dioxide, carbon monoxide, and water.

3. The method of claim 1 , wherein:
contacting the first-reactor effluent with the second ODH catalyst in the second reactor further forms acetic acid.

4. The method of claim 1 , further comprising adding carbon dioxide to the second reactor to favor production of acetaldehyde over production of ethanol.

5. The method of claim 1 , further comprising separating the second-reactor effluent into a liquid stream and a gas stream, wherein the liquid stream comprises the ethanol, the acetaldehyde, acetic acid, and the water, and the gas stream comprises the ethylene, ethane, the carbon dioxide, and carbon monoxide.

6. The method of claim 5 , further comprising:
using a packed column to separate the second-reactor effluent into the gas stream and the liquid stream in a packed column;
discharging the gas stream overhead from the packed column; and
discharging the liquid stream from a bottom portion of the packed column.

7. The method of claim 6 , further comprising diverting a portion of the modified first-reactor effluent to the packed column instead of to the second reactor, wherein:
the first ODH catalyst in the first reactor and the second ODH catalyst in the second reactor each comprise a mixed metal oxide having formula Mo a V b Te c Nb d Pd e O f ;
a, b, c, d, e, and f subscripts are relative atomic amounts of elements Mo, V, Te, Nb, Pd, O, respectively; and
when a=1, b=0.01 to 1.0, c=0.01 to 1.0, d=0.01 to 1.0, 0.00≤e≤0.10, and f is a number to satisfy at least the valence state of the corresponding elements in the catalyst.

8. The method of claim 1 , wherein:
the first reactor comprises the first ODH catalyst in a fixed bed;
the second reactor comprises the second ODH catalyst in a second fixed bed;
contacting the modified first-reactor effluent with the second ODH catalyst in the second fixed-bed reactor produces acetic acid; and
the second-reactor effluent further comprises carbon monoxide.

9. The method of claim 1 , wherein removing oxygen from the first-reactor effluent upstream of the second reactor comprises flowing the first reactor effluent through an oxygen-separation vessel comprising a selective oxidation catalyst to remove oxygen from the first reactor effluent to provide the modified first-reactor effluent.

10. The method of claim 1 , wherein the first ODH catalyst is a first fluidized bed of catalyst and the second ODH catalyst is a second fluidized bed of catalyst.

11. The method of claim 1 , wherein the first-reactor effluent further comprises carbon monoxide, acetic acid, and unreacted ethane.

12. The method of claim 11 , further comprising:
maintaining an operating temperature of the first reactor at less than 450° C.; and
maintaining an operating temperature of the second reactor at less than 450° C.,
wherein the second-reactor effluent further comprises carbon dioxide, carbon monoxide, and water.

13. The method of claim 11 , further comprising:
maintaining an operating temperature of the first reactor at less than 450° C.; and
maintaining an operating temperature of the second reactor at less than 450° C.,
wherein the second-reactor effluent further comprises carbon monoxide.

14. The method of claim 11 , wherein:
contacting the first-reactor effluent with the second ODH catalyst in the second reactor further forms acetic acid.

15. The method of claim 11 , further comprising adding carbon dioxide to the second reactor to favor production of acetaldehyde over production of ethanol.

16. The method of claim 11 , further comprising separating the second-reactor effluent into a liquid stream and a gas stream, wherein the liquid stream comprises the ethanol, the acetaldehyde, acetic acid, and the water, and the gas stream comprises the ethylene, ethane, the carbon dioxide, and carbon monoxide.

17. The method of claim 16 , further comprising:
using a packed column to separate the second-reactor effluent into the gas stream and the liquid stream in a packed column;
discharging the gas stream overhead from the packed column; and
discharging the liquid stream from a bottom portion of the packed column.

18. The method of claim 11 , wherein removing oxygen from the first-reactor effluent upstream of the second reactor comprises flowing the first reactor effluent through an oxygen-separation vessel comprising a selective oxidation catalyst to remove oxygen from the first reactor effluent to provide the modified first-reactor effluent.

Assignees

• Nova Chem Int Sa

Inventors

• Simanzhenkov Vasily
• Goodarznia Shahin

Classifications

• C07C27/12 Primary

  with oxygen · CPC title

• C07C5/48 Primary

  with oxygen as an acceptor · CPC title

• C07C2523/28

  Molybdenum · CPC title

• C07C2523/22

  Vanadium · CPC title

• C07C2523/32

  Manganese, technetium or rhenium · CPC title